Field of the Disclosure
The present disclosure relates to an information obtaining apparatus, an image capturing apparatus, and a method for obtaining information.
Description of the Related Art
Apparatuses capable of capturing images of organizational structures, vascular structures, and others in living bodies include, for example, magnetic resonance imaging (MRI), and x-ray computed tomography (X-ray CT). However, these methods have issues in usage of contrast agents, radiation exposure, and the like, and thus observation methods are expected which prevent radiation exposure and are not invasive. There are measuring techniques using light as measuring methods which prevent radiation exposure and are not invasive.
However, living bodies are strong scatterers with respect to light, and in observation of tissues in the living bodies using light, scattered light causes blurring of organizational structures or lowering of image contrasts. Thus, in the observation of blood vessels such as thin blood vessels which easily cause lowering of contrasts due to scattering and new blood vessel groups which absorb less light and are low in contrasts, it is required to extract and emphasize blood vessel images.
International Publication No. WO 2013/088566 describes a technique for extracting a blood vessel pattern of a vein using a filter reducing frequency components lower and higher than a spatial frequency of the vein in a field of the vein authentication.
However, it is highly likely that an image of the new blood vessel group or the like has a low spatial frequency, and when the method according to International Publication No. WO 2013/088566 is used, it is difficult to extract a pattern of the new blood vessel group. Thus, a technique is required which can obtain information about a blood vessel with high accuracy regardless of a spatial frequency of a blood vessel image.
Accordingly, there is a need for an information obtaining apparatus that can obtain information about a blood vessel with high accuracy.